Drive and control system for looms



Oct. 15, 1968 JUILLARD DRIVE AND CONTROL SYSTEM FOR LOOMS Original FiledSept. 15, 196A 4 Sheets-Sheet 1 Oct, 15, 1968 Y. JUILLARD 3,405,740

DRIVE AND CONTROL SYSTEM FOR LOOMS Original Filed Sept. 15, 1964 4Sheets-Sheet 2 1 m I "3 we I J -W-F s: l 5

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Yl/[S JU/ZZ/IR Oct. 15, 1968 Y. JUILLARD 3,405,740

DRIVE AND CONTROL SYSTEM FOR LOOMS Original Filed Sept. 15. 1964 4Sheets-Sheet 5 FIGS Oct. 15, 1968 Y. JUILLARD DRIVE AND CONTROL SYSTEMFOR LOOMS 4 Sheets-Sheet 4 INVENTOR YVES JU/LLARD wmmvkmok OriginalFiled Sept. 15, 1964 United States Patent m 3,405,740 DRIVE AND CONTROLSYSTEM FOR LOOMS Yves Juillard, Mulhouse, Haut-Rhin, France, assignor toSociete Alsacienne de Constructions Mecaniques, Mulhouse, Haut-Rhin,France, a company of France Continuation of application Ser. No.396,611, Sept. 15, 1964. This application Aug. 19, 1966, Ser. No.573,723 Claims priority, applicgatioir grancc, Sept. 20, 1963,

9 Claims. ((21. 139-1 ABSTRACT OF THE DISCLOSURE Prior applications Thisapplication is a continuation of my prior application Ser. No. 396,611,filed Sept. 15, 1964, now abandoned.

It is the general object of this invention to provide an improved systemfor driving the various components of a loom, and for controlling themovements thereof. Features of this improved system include its greatlyincreased flexibility and the great ease with which certain componentsof the loom can be operated in reverse, or backed up in order to removedefective weft threads from the woven fabric and for similar correctivepurposes. It is a specific object of the invention to provide a loomdrive system in which the drive connections for the harness means andheddles serving to part the warp into a shed at each weaving cycle, canbe effectively disengaged from the drive connections for the batten andweft shooting means serving to shoot a pick of weft through the shed ateach cycle and beat the weft up into the warp, when such disengagementis desired.

This makes it possible to operate the heddles in reverse while thebatten and Weft shooting means remain stationary, as for releasing adefective pick of weft previously woven into the fabric. A relatedobject is to ensure that the performance of such correcting operationswith the batten and weft shooting means held stationary, will not impairthe correct timing relationship bet-ween the movements of the harness onthe one hand, and the batten and weft shooting means on the other, andthat the pattern and other characteristics of the weave will not beaffected.

The invention essentially comprises, in a loom comprising a frame, meansfeeding warp threads longitudinally of the frame, means supplying weft,cyclically operable Weaving mechanism including shed forming means,transversely reciprocable means for shooting weft through the shed andlongitudinally reciprocable batten means including a reed, the provisionof a reversibly powerdriven rotatable primary drive member, a firstdrive member rotatable on the frame and drivingly connected forreciprocating the batten and weft shooting means, a second drive memberrotatable on the frame from the powerdriven member and dn'vinglyconnected to the primary drive member for operating the shed formingmeans independently of the batten and weft shooting means, and adisengageable drive coupling between the primary and second drivemembers which is operative in a predetermined relative angular positionof the first and second drive members.

3,405,740 Patented Oct. 15, 1968 The loom is thus enabled to operate inthe normal manner when the coupling is engaged and the power drivermember is rotated in the forward direction, and is also capable ofreverse operation for Weave-correcting purposes when the coupling isdisengaged and the power driven member is rotated in the reversedirection; at such time the heddles are reciprocated in reverse phase,but the batten and weft shooting means (such as weft picking needlesreciprocable on the batten) are held stationary, in a suitable positionrelative to the frame.

The various objects, features and advantages of the invention will nowbe described in greater detail with reference to an exemplary embodimentselected by way of illustration but not of limitation and shown in theaccompanying drawings, wherein:

FIG. 1 is a side elevational view showing the main components of animproved loom embodying the invention; the loom being of the so-calledshuttleless type in which the Weft is shot across the shed in the warpby a pair of cooperating transversely reciprocated needles carried bythe batten.

FIG. 2 is a top plan view of the loom partly broken away and shown insection on the line IIII of FIG. 1.

FIG. 3 is an enlarged fragmentary elevational view of part of themechanism including the disengageable coupling in the normal weavingcondition.

FIG. 4 is a view similar to FIG. 3 showing the same mechanism duringun-weaving or backing up operation; and

FIG. 5 is a circuit diagram of the electrical control system.

The loom schematically illustrated in FIGS. 1 and '2 is of a generaltype similar to the one described in French Patent 1,290,867 and in mycorresponding US. Patent No. 3,159,186, issued on Dec. 1, 1964. Itschief components include a main frame 1, a batten assembly 2 pivotedabout a lower horizontal transverse shaft 3, and a reed 4 (FIG. 2)supported by the batten. Also supported from the batten are a piar ofweft shooting needles including the weft-inserter needle 6 and thedrawing needle 7 which cooperate in conventional manner to shoot a pickof Weft thread through the shed formed in the 'warp threads during thecourse of each weaving cycle. As described in greater detail in theabove noted pat ents, both other, transversely of the batten, withinserter needle 6 engaging at its inner end a portion of weft threadconnected to a supply (not shown), and the drawing needle 7 acting topick up this weft thread from the needle 6 as the two needles meet nearthe midpoint of the transverse width of the shed, and after thistransfer has been made both needles 6 and 7 are moved away from eachother so that needle 7 now carries the Weft thread through the remainderof the width of the shed. The reed 4 carried by the batten then acts topress home or beat up this newly shot pick of Weft against thepreviously Woven weft threads to provide a new increment of wovenfabric.

Means for actuating the weft shooting needles 6 and 7 are schcmaticallyshown as including respective linka es 11 (associated with needle 7) and12 (associated with needle 6). connected for operation from respectivecams 13 and 14 mounted on opposite end portions of a crankshaft 15journalled transversely in frame 1. Crankshaft 15 also acts to impartpivotal reciprocation to the bat en 2 by way of a pair of connectingrods 18-19 having their one ends pivoted to respective arms 18a, 19aprojecting from the upper end of the batten and their other ends pivotedto the cranks of shaft 15.

A conventional loom harness 21 is shown as including the pair ofreversely vertically reciprocating heddles 22 and 23. The means foreciprocating the heddles comprises levers, 24, 25 having their one endspivoted to the lower ends of the heddles and their other ends pivoted ona common transverse pivot a of the frame 1. The levers 24, 25 areengaged at points intermediate their ends by respective excentric earns26, 27 secured on a common transverse shaft 28, driven in a manner laterdescribed.

A warp beam 34 is shown supported on a transverse shaft 34a near therear end of the loom, and provided with conventional retarding weightmeans 35. Numeral 31 designates warp threads extending upward from thewarp beam 34, over a warp guide roll 32 and warp carrier 33. Beyond orforward of carrier 33, the warp threads are parted in the usual mannerto form a shed. That is, alternate warp threads are passed through loopscarried by the respective heddles 22 and 23, so as to provide a shedformed by upper and a lower sheets of warp 31 and 31". As the heddles22, 23 are vertically reciprocated moving in opposite directions, therelationship between the upper and lower sheets 31', 31 reverses duringeach weaving cycle, thereby reversing the shed. Forwardly of theheddles, the weft shooting needles 6, 7 operate as indicated above toshoot a pick of weft thread through the shed during each cycle. Beforethe shed is reversed by the movement of the heddles the batten 2 movesforward so that the reed 4 heats up the newly shot weft thread. In thisway, there is formed a web of fabric indicated at 37, which is taken upby a conventional take up or reel mechanism designated generally as 38.

A reversible electric motor shown as separately mounted near the inputend of the loom and carries a drive pulley 46 connected by twin belts 47with a larger diameter driven pulley 48 mounted for free rotation on onelaterally projecting end of crankshaft 15. Driven pulley 48 is large andheavy in order to act as a flywheel. Driven pulley 48 may be termed theprimary drive member of the system of the invention. The driven pulley48 has a tubular hub 48a surrounding the crankshaft 15 and, formedintegrally with this hub, is a drive wheel 52. A sprocket chain 53connects sprocket wheel 52 with a largerdiameter sprocket wheel 50secured to the transverse shaft 28 which carries the cams 26, 27operating the needles 22, 23 of harness 21. Shaft 28 may also serve tooperate any pattern mechanism, such as weft selector positioningmechanism if provided.

The driven pulley 48 and sprocket wheel 52 can be coupled for rotationwith and uncoupled from the crankshaft 15 by means of a coupling devicedesignated generally as 54. This includes a disc 51 integrally formedwith the hub 48a of pulley 48 coaxially with said pulley and withsprocket 52, as shown in FIGS. 3 and 4, disc 51 has a notch 57 formed inits periphery. An arcuate pawl member 55 is mounted by means of a pivot56 on one side of the weft shooting cam 13 which is fast on crankshaft15 and controls the movement of weft inserter needle 6 as earlierindicated. Pawl 55 has a tooth 55a engageable with the notch 57 and isyieldably urged in rotation about pivot 56 in the direction to effectsuch engagement by means of a helical tension spring 58 having its endsattached to pins 61 and 62 mounted on cam 13 and on a finger 63projecting from pawl 55, respectively. Pawl 55 further includes anarcuate extension 55b on its end remote from tooth 55a, the concavesurface of said extension being shaped to bear slidably against thecylindrical periphery of disc 51 when the pawl tooth 55a is disengagedfrom notch 57, as shown in FIG. 4.

A stop lever 65 is pivoted on a horizontal transverse pivot 66 on frame1 and is rotatable between an inactive position shown in full lines inFIG. 3 and an active position shown in FIG. 4. In its idle position(FIG. 3) the free end of stop lever 65 is positioned radially beyond thecircular path of travel of the extremity of pawl finger 63, whereas inits active position (FIG. 4) the free end of the stop lever isinterposed in the path of travel of said finger 63. Stop 65 is normallyretained in its idle position by means of a normally energizedelectromagnet E1 having its armature connected to the stop lever 65. Ondeenergization of the electromagnet E1, stop lever 65 is moved to itsactive position by a helical compression spring 65a.

A stationary stop 67 is secured to the frame 1 at a position arcuatelyspaced somewhat forwardly from the free end of stop lever 65, and atsuch a radial distance from the axis of shaft 15 that, when pawl tooth55a is engaged in notch 57 as in FIG. 3, stop 67 is clear of thecircumferential path of the extremity of pawl finger 63, whereas whenthe pawl tooth 55a is disengaged from notch 57 as in FIG; 4, the freeend of the finger 63 will engage stop 67. As will appear later, whenshaft 15 and pulley 48 are rotated by motor 45 in reverse, i.e.,counterclockwise as shown in FIGS. 1, 3 and 4, the pawl finger 63 can beinterposed and trapped between the movable stop 65 when advanced to itsactive position, and the fixed stop 67, as shown in FIG, 4.

A lockout switch S1 is mounted on the frame and has an actuator memberwith a roller 71 projecting therefrom towards crankshaft 15, thearrangement being such that when the pawl tooth 55a is out of the notch57 (the position shown in FIG. 4) the free end of finger 63 can actuateroller 71 to open the normally closed lockout switch S1 as will later beexplained.

The crankshaft 15 carries a cam disc 73 having smallerand larger-radiusparts 73a and 7317, respectively. A normally closed reverse lockoutswitch S2 is mounted on a switch carrying lever 76 pivoted at 77 to thefixed frame structure. Lever 76 is pivotable between an inactiveposition shown in FIG. 3 and an active position shown in FIG. 4. In theinactive position of lever 76 the actuator roller 74 of reverse lockoutor reverse limiting switch S2 is clear of the path of the periphery ofthe larger-radius part 73b of cam 73 whereas in the active position oflever 76 switch actuator roller 74 is cammed by part 73b to open thenormally-closed reverse operation limiting switch S2. Lever 76 alsocarries a positioning switch S3, which, in the active (but not theinactive) position of lever 76 is acted on by a camming boss 75projecting from a side of disc 51 to actuate the switch S3.

Lever 76 is retained in its inactive position (FIG. 3) by a normallyenergized electromagnet E2 whose armature 76a is connected by a link 78with lever 76. When electromagnet E2 is deenergized, biassing means (notshown) move the lever 76 to its active position.

In normal operation of the loom, both electromagnets E1 and E2 areenergized, so that movable stop 65 is held clear of the path of pawlfinger 63 and both switches S2 and S3 remain continuously in theirnonactuated conditions throughout each revolution of the crankshaft 15.

In the electrical control circuit of FIG, 5, the reversible electricmotor 45 is shown connected for energization from a three-phase powersupply comprising condoctors 93, 94 and 95. The motor 45 is energizedthrough a reversing type motor controller designated generally as 100.The controller comprises a forward contactor portion 101 and a reversecontactor portion 102.

The forward contactor 101 includes an operating magnet 104 having anenergizing winding 105. The magnet 104 controls three sets of normallyopen heavy duty contacts 106, 107 and 108 which supply current to themotor 45 for operation in the forward direction. A set of auxiliarycontacts 109 is also controlled by magnet 104. The contacts 109 areclosed and opened along with the heavy duty contacts 106, 107 and 108.

The reverse contactor 102 includes an operating magnet 110 having anenergizing winding 111. The magnet 110 controls three sets of heavy dutycontacts 112, 113 and 114 together with a set of auxiliary contacts 115.The auxiliary contacts 109 of forward contactor 101 are connected inmultiple with the auxiliary contacts 115 of reverse contactor 102.

The motor 45 is of the type which has a brake associated therewith forstopping the motor abruptly when the power is shut off. The brakecomprises a brake drum 117 connected to the shaft of motor 45 asindicated diagrammatically by the dashed line 118. A brake shoe 119 isengageable with the drum 117. The brake shoe 119 is carried by a pivotedlever 120 and is yieldingly urged toward its braking position by atension spring 121. The brake shoe 119 is disengaged from the drum 117by energization of a solenoid operating winding 123 the armature 124 ofwhich is connected to the lever 120. The winding 123 is energized from asource of low voltage 125 shown illustratively as a grounded battery. Atransformer secondary winding may constitute the low voltage source 125,if desired. A circuit from low voltage source 125 extends through thenormally closed contacts 126 of a STOP push button 127 and a conductor128 to the auxiliary contacts 109 and 115 of forward and reversecontactors 101 and 102, respectively. When either of contactors 101 or102 is energized to operate the motor 45, the circuit is extendedthrough a conductor 130 to energize winding 123 and release the brakedrum 117.

The normally open contacts 131 of a manually operable START push button132 are arranged to energize the operating winding 134 of a lockingrelay 135. The contacts 131 are energized from the low voltage source125 through STOP button contacts 126, conductor 128, normally closedrelay contacts 136 of a warp-break relay 137, normally closed contacts138 of a weft-break relay 139, and contacts 140 of the lockout switchS1. When all of these contacts are closed, as shown, operation of STARTbutton 132 energizes the winding 134 of locking relay 135 and closure ofits contacts 142 locks the relay in.

Closure of contacts 143 of locking relay 135 connects the low voltagesource 125 to energize the solenoids E1 and E2. Closure of contacts 144of locking relay 135 energizes the winding 105 of forward contactor 101from the low voltage source 125 through normally closed contacts 145 ofa weft-break switch 146, normally closed contacts 147 of a warp-breakswitch 148, conductor 128 and normally closed STOP button contacts 126.The warp-break switch 148 includes a normally open contact 149 connectedto energize warp-break relay 137 which holds in through its lockingcontacts 150.

The weft-break switch 146 includes a normally open contact 152 connectedto energize the Witt-break relay 139 which holds through its lockingcontacts 153.

A correction relay 154 comprises a pair of normally open controlcontacts 155 and a pair of locking contacts 156. The relay 154 iscontrolled by the normally closed and normally open contacts 158 and159, respectively, of positioning switch S3. The control relay 154 isfurther associated with a forward jogging button 160 and a reversejogging button 161. The forward button 160 is provided with normallyopen contacts 162 and normally closed contacts 163. Similarly, thereverse button 161 is provided with normally open contacts 164 andnormally closed contacts 165. The normally open contacts 164 of reversebutton 161 are connected through the contacts 167 of reverse lockoutswitch S2 to the winding 111 of reverse contactor 110.

Switches 148 and 146 are single-pole double-throw loom-actuated switcheswhich respectively control the energization of warp break and weft-breakrelays 137 and 139. Breakage of any warp or weft yarn, respectively,momentarily actuates switch 148 or 146 to its off-normal position inwhich the pair of contacts 149 or 152 is closed to energize relay 137 or139, respectively. Energization of either relay is thereafter maintainedthrough hold contacts 150 or 153.

To start the loom into normal operation, wherein motor 45 must revolvein the forward direction, manual start switch 132 is first depressed,thereby completing an energizing circuit for locking relay winding 134as previously described.

Energization of winding 134 closes contacts 144, 142 and 143. Closure ofcontacts 144 completes an energizing circuit for the forward-drivecontactor winding through stop switch 127 and weft yarn-break switches148 and 146 both in the normal positions shown, now-closed contacts 144and winding 105. Energization of contactor winding 105 closes its threepoles 106, 107 and 108 to apply three-phase power to the motor 45 in theforward sense of rotation.

Closure of contacts 142 provides a holding circuit for locking relay135, and closure of contacts 143 energizes both electromagnets E1, E2connected in parallel. As earlier explained, energization of magnet E1retracts movable stop 65 clear of the path of pawl finger 63, whileenergization of magnet E2 retracts lever 76 to withdraw both switches82, S3 out of the paths of their respective actuating cams 75, 73. Asearlier noted, energization of forward-drive contactor winding 105closes auxiliary contacts 109, energizing the brakemagnet 123 to retractbrake shoe 119 from brake drum 117.

In these conditions, motor 45 rotates in the forward direction andthrough drive belts 47 rotates the driven pulley 48 and with it couplingdisc 51. As soon as the notch 57 in the disc moves past pawl tooth 55athe tooth drops into the notch under the bias of spring 58, coupling cam13 and hence crankshaft 15 with the drive pulley 48. Bodily rotation ofthe crankshaft 15 with the driven pulley 48 continues in the forwarddirection to reciprocate the batten 2 and operates the various loommechanisms as earlier described.

When it is desired to stop the normal operation of the loom, manual stopbutton 127 is momentarily depressed, cutting off wire 128 from lowvoltage supply 125. This deenergizes the locking relay so that contacts144, 142, 143 are opened. Opening of the locking contact 142 ensuresthat relay 135 is not reenergized on release of stop switch 127. Openingof contact 144 deenergizes forward-drive contactor winding 105 so thatcontacts 103, 107, 108 open, cutting off the supply to the motor 45, andauxiliary contacts 109 open, deenergizing the brake electromagnet 123and applying brake shoe 11-9 to motor brake drum 117. The heavy drivenpulley 48 is thus rapidly stopped. The opening of contacts 143deenergizes both electromagnets E1 and E2 so that levers 65 and 76 areyieldingly moved to their active positions Without any immediate result.

If during the normal operation of the loom, a break occurs in a Warpthread, the warp-break switch 148 is at least momentarily actuated toopen contacts 147 and close contacts 149. Opening of contacts 147 cutsoff the flow of current from wire 128 through forward-drive contactorwinding 105, thereby stopping and braking the motor 45. Simultaneouslyclosure of contacts 149 energizes warp-break relay 137, which closeshold contacts to maintain the relay 137 energized and opens contacts 136to deenergize locking relay 135 with the same results as earlierdescribed, including the opening of contacts 144 to preventreenergization of the forward-drive contactor winding 105 on subsequentreturn of switch 148 to its initial right-hand position.

It should be noted, in this connection, that the yarnbreak switch 148may return very quickly to its initial or normal condition, in a matterof a few hundreths of a second, since the broken warp yarn may very welltangle up promptly with adjacent yarns and rapidly become taut again.The relays 137, 139, 135, 154 should therefore be of a fast-acting typewith a response time of the order of 10 milliseconds. The motor drivecontactors such as 101 will generally be much slower acting,

7 tacts 136. Thereafter, operation of start switch 132 will energizelocking relay winding 134 and close contacts 144, whereupon the forwardrotation of motor 45 will be resumed.

A generally similar sequence of events occurs in the case of weftbreakage. Weft break switch 146 is displaced leftwardly to open itscontacts 145 and close contacts 152. Opening of 145 deenergizes forwarddrive contactor 101 and closure of contacts 152 energizes weft-breakrelay 139, which remains energized due to closure of its hold contacts153. Contacts 138 are opened, deenergizing locking relay 135, whosecontacts 144, 142, 143 open. Opening of contacts 144 preventsreencrgization of forward-drive motor contactor 101 should the weftbreak switch 146 be quickly returned to its initial position, as wouldbe the case if the weft yarn were to break just after it has been shotthrough the shed. Again, re-starting the loom after repair of the weftrequires preliminary depression of the stop switch 127 to deenergize theweft break relay 139.

In accordance with the invention, in the case of breakage or otherdefect in the weft thread, it is possible to operate the motor 145 inrevere, so as to back up the harness and heddles without moving thebatten and weftpicking needles, thereby enabling one or more defectiveReferring to FIG. 3, it is first indicated that the purpose of the cam73 secured to crankshaft 15, and the reverse operation lockout switch S2cooperating with that cam, is to prevent backing up operations frombeing initiated whenever the crankshaft has happened to stop within anunfavourable range of angular positions, more precisel a range ofangular positions such that the batten 2 is positioned at a relativelyadvanced point in its forward reciprocating stroke, weft picking needles6, 7 are not fully withdrawn out of the shed, and heddles 22, 23 are notappreciably displaced with respect to each other so that the shed isrelatively closed. If this is the case, then the larger-radius sector73b of cam 73 is positioned to engage the actuator roller 74 of reverselockout switch S2 (it must be recalled that, in the stationary conditionof the loom, the electromagnet E2 is deenergized so that lever 76 movesinto its active position). This situation will be dealt with later.

There will first be considered the situation in case of weft breakagewhere the crankshaft has come to a stop in its reversible range ofangular positions, for instance as indicated in FIG. 4. In this case thesmallerradius sector 73a of cam 73 is presented to the limiting switchS2. The probability of thread breakage is greater in the reversible openshed portion of the weaving cycle than in the closed shed portionbecause of the greater stresses which are then applied to the threadswhen the shed is open.

It will be recalled that the thread breakage stopping of motor isaccompanied by deenergization of the locking relay 135, so that contacts144, 142, contacts 143 are open. Opening of 143 has deenergized bothelectromagnets E1, E2 so that stop lever 65 is rotated to its activeposition and lever 76 is simultaneously rotated to its active position(see FIG. 4). Lockout switch S1 is still in its normally closed position(FIG. 3) and reverse lockout switch S2 is also in its normally closedposition under these conditions. If the crankshaft 15 has come to restin the angular position shown in FIG. 3, but with the lever 76 in itsactive position, cam boss 75 engages actuator roller 72, so that thesingle-revolution or positioning switch S3 is in its actuated positionin which contacts 158 are open and 159 closed. The closure of contacts159 will energize correction relay 154, through 163, 165, 159 and stopswitch 127. This energization is maintained by the holding contacts 156,through contacts 159 and 126.

The nonlocking manual reverse button 161 is then depressed, closingcontacts 164 and opening contacts 165. Closure of con.acts 164 energizesreverse drive contactor 102 through the circuit path including closedreverse lockout switch contacts 167 of S2, 164, 155 from the energizedrelay 154 and the closed contacts of stop switch 127. The reverse drivecontacts 112, 113, 114 are thereby closed together with auxiliarycontacts 115. Closure of auxiliary contacts energizes the brake magnet123, thus releasing the motor brake 117, 119. Motor 45 and coupling disc51 start rotating in the reverse sense (counterclockwise in FIGS. 1, 3and 4). Cam 13 and crankshaft 15 are temporarily rotated in reversealong with coupling disc 51 since pawl tooth 55a is held in engagementwith notch 57 by spring 58. Shortly before the point in the revolutionof disc 51 where pawl finger 63 would strike movable stop 65, which isthen in its active posi tion, cam boss 75 moves past roller 72 andactuates positioning switch S3 to open contacts 159 and close contacts158. The opening of contacts 159 cuts off the energizing circuit forcorrection relay 154 whose contacts open and break the energizingcircuit of reverse drive contactor 102, so that motor 45 is temporarilydeenergized and braked, until contacts 158 close and reestablish acircuit permitting the energization of reverse drive contactor 102 byoperation of the reverse button 161 to close its contacts 164.

The motor 45 is now again set into reverse rotation. Shortly thereafter,pawl finger 63 strikes the movable stop 65. Cam plate 13, and hencecrankshaft 15, can therefore revolve no further whereas disc 51continues its reverse rotation; pawl 55 is rotated about pivot 56against the yielding action of spring 58 so as to disengage its tooth55a from notch 57 and assume the position shown in FIG. 4.

It will be understood that in the above described operation, thepositioning switch S3 (and its actuating cam 75) has served to stop thedriving of pulley 48 in the reverse direction momentarily just ahead ofthe point where pawl finger 63 strikes stop 65, with the result thatfinger 63 strikes stop 65 while moving at very low velocity withconsequent reduction in the impact applied to the parts involved.

The reverse rotation of disc 51 continues while cam 13 and crankshaft 15remain stationary with pawl tooth 55a and extension 55b both riding theperiphery of revolving disc 51, and pawl finger 63 trapped between stops65 and 67. The position of movable stop 65 is such that the angularposition in which crankshaft 15 is thus arrested by pawl finger 63striking movable stop 65 is the position in which the shed is open, thebatten being stopped with the reed away from the feel of the fabric andweftshooting needles 6, 7 being positioned clear of the shed.

Pawl finger 63 acts on roller 71 to open lockout switch S1, thuspreventing any possibility of energizing motor 45 for forward drivethrough inadvertent depression of normal manual start switch 132.

As pulley 48 revolves in the reverse direction, it operates through thedrive comprising drive sprocket 52, chain 53, driven sprocket 50, camshaft 28, cams 26-27 and levers 24-25. This operates harness mechanism21, so that heddles 22, 23 are reciprocated in reverse phase orunweaving direcion with respect to the batten and weft insertingmechanism. This is the direction required for disengaging any defectiveweft from the web, while the batten and needles remain stationary.

Shortly before notch 57 in coupling disc 51 again moves in the reversedirection past pawl tooth 55a after one full counterclockwise revolutionin the uncoupled condition, cam boss 75 again actuates the positioningswitch S3, opening contacts 158 and closing contacts 159. This againcuts the energizing circuit for reverse drive contactor 102 and themotor 45 is deenergized and braked, contact 155 being unable to reclosebecause the energizing circuit of correction relay 154 is interrupted by9 the open contacts 165 of the depressed reverse plugging switch 161.

The operator now releases the non-locking reverse switch 161. Thisenergizes relay 154 by way of contacts 59, 163 and 165 and closes holdcontacts 156 so that the correction relay 154 remains energized and alsocloses its contacts 155. However this does not reenergize reversedrivecontactor 102 since contacts 164 now are open due to release of reversebutton 161.

The operator can now proceed to remove the broken or otherwise defectiveweft thread, now disengaged from the web by re-opening of the shed.Should there be more than one defective weft thread, it is simplynecessary to depress the nonlocking reverse button 161 successively asmany times as required. At each continuous depression of reverse button161 the pulley 48 rotates through one full revolution in reverse, movingthe heddle-harness and pattern control mechanism backwards one cycle butleaving the batten stationary, and after each such continuous depressionthe switch 161 is released and the defective pick removed from thefabric. The weft pattern and other characteristics of the weave areunaffected regardless of their complexity, and the loom remains at alltimes ready to resume normal weaving operations.

After the defects in the weft have been corrected and it is desired toresume the normal weaving process, it is first necessary to depress thenonlocking forward button 160. This closes contacts 162 and opens 1-63.Closure of contacts 162 energizes forward drive contactor 101 through162 and through contacts 155 which are closed at this time sincecorrection relay 154 still remains energized by way of contacts 156 and159. Motor 45 is therefore started in the forward direction to rotatepulley 48 and disc 51 in the clockwise direction indicated by arrow f1.As cam boss 75 disengages switch actuator 72 contacts 158 close and 159open. Opening of contacts 159 deenergizes correction relay 154, openingcontacts 155, however closure of contacts 159 provides an alternativecircuit path for continued energization of forward-drive contactor 101through closed contacts 162 so that the forward rotation of motor 45continues.

As the pulley 48 completes substantially one revolution and a shortwhile before notch 57 is presented to pawl tooth 55a, cam boss 75reengages the positioning switch actuator 72, opening contacts 158 andclosing 159. Opening of contacts 158 now deenergizes forward-drivecontactor 101 since the correction relay 154 is deenergized and it isnoted that closure of contacts 159 cannot reenergize relay 154 sincecontacts 163 are open owing to continued depression of forward button160. The motor 45 is therefore stopped. The non-locking forward buttonor switch 160 is released and again depressed. The momentary release ofthe forward button 160 has served to close contacts 163 and thusenergize correction relay 154 so that its contacts 156 and 155 close. Onrenewed depression of forward button 168, correction relay 154 remainsenergized through its closed hold contacts 156, while the closedcontacts 155 now provide an alternative path for energization of forwarddrive contactor 101 so that motor 45 resumes its forward rotation. Thusnotch 57 is brought into register with pawl tooth 55a while therevolving parts are moving at low speed, and the engagement of the pawltooth 55a with the notch 57 is effected in a smooth manner. Pawl finger63 releases switch actuator roller 71 so that lockout switch S1 isrestored to its normally closed position. Normal conditions are thusreestablished, and manual start switch 132 can be depressed to resumethe normal Weaving process as described above.

The situation previously referred to will now be described wherein theangular position of crankshaft 15 at the time its normal rotation wasarrested is such that the large-radius sector 73b of cam 73 is presentedto switch actuator roller 74 so that the reverse lockout switch S2 isopen. It will be recalled that the function of cam 73 and reverselockout switch S2 is to prevent the backing or reversing movement to bestarted with the shed substantially closed. Since the reverse lockoutswitch S2 is now open, reverse drive contactor 102 cannot be energizedby depression of the nonlocking reverse button 161 and the depression ofthis button or switch if attempted, would be ineffective. In theseconditions it is necessary first to depress momentarily the nonlockingforward switch 160. This causes closure of contacts 162 which energizesthe forward-drive contactor 101 by Way of positioning switch contacts158 which are closed at this time. It is evident from FIGS. 3 and 4,that when cam sector 73b actuates roller 74, the positioning cam boss 75does not engage roller 72. The motor 45 and pulley 48 are, therefore,rotated in the forward direction. As cam surface 73b disengages roller74, positioning switch S2 first closes, and shortly afterwards cam boss75 engages roller 72 to actuate the positioning of switch S3. Opening ofcontacts 158 deenergizes the forward drive contactor 101 and the motor45 and pulley 48 are stopped. Nonlocking forward switch 160 is nowreleased, closing contacts 163 so that relay 154 is energized by way ofswitch contacts 159 which have just been closed. Correction relaycontacts close, but since contacts 162 are now open du to release ofswitch 160 the forward-drive contactor 101 is not reenergized.

At this time the parts are positioned as described in the instance firstassumed for FIG. 4 and the previously described reverse operationprocedure can be followed by successive actuations of the nonlockingreverse switch 161 to effect one or more reverse cycles of the harnessand pattern control mechanism operation While the batten andweft-pickers remain stationary, in order to correct any defects in theweft.

To summarize, in case of breakage or other defect in the weft, theinvention provides means for permitting imparting reverse rotation, onerevoltuion at a time, to the drive pulley driving the loom harness andother weft pattern control mechanism while holding the batten andweftinserting means stationary. After each such reverse revolution, thedefective weft can be withdrawn. When the normal forward movement of theloom is thereafter resumed, the positions of the loom components at theinstant the first new pick of weft is inserted are identically the sameas at the instant the first defective pick of weft was inserted.

While I have shown and described what I believe to be the bestembodiments of my invention, it will be apparent to those skilled in theart that various changes and modifications may be made therein withoutdeparting from the spirit and scope of the invention as defined in theappended claims.

What is claimed is:

1. A loom comprising in combination:

a frame;

means supplying warp threads longitudinally of the frame;

cyclically operable weaving mechanism including shed forming meansacting on said warp threads;

longitudinally reciprocable batten means;

weft shooting means carried by the batten means for shooting weftthrough the sheds; and

reed means on the batten means;

a reversible rotatable power-driven member mounted on said frame;

a first drive member rotatable on said frame and drive connectionstherefrom for simultaneously operating said batten means and weftshooting means;

a second drive member rotatable on said frame in unison with saidpower-driven member and drive connection therefrom for operating saidshed-forming means;

disengageable coupling means connecting said powerdriven member to drivesaid second drive member, said coupling means being engageable anddisengageable in predetermined relative angular positions of said drivemembers with respect to said frame and wherein the shed is open, saidreed means is remote from the fell of the fabric and said weft shootingmeans is clear of the shed;

releasable means operative during forward rotation of the power-drivenmember for continuously maintaining said coupling means engaged fornormal weaving operation;

releasing means operative during reverse rotation of said power-drivenmember for actuating said releasable means to disengage said couplingmeans when said first and second members are in said predeterminedpositions;

an electric circuit comprising a reversible motor connected to drivesaid power-driven member;

contactor means included in said circuit for selectively energizing saidmotor for operation in either direction; and

manually actuable circuit means including switch means controlled bysaid second drive member for operating said motor to cause a singlecomplete revolution of said second drive member in the reverse directionwith said first drive member stationary in said predetermined position,said single revolution being accompanied by a single shed-formingoperation of said shed-forming means whereby a previously woven weftthread is released.

2. The loom defined in claim 1, wherein said disengageable couplingcomprises:

adjacent first and second coupling members respectively connected forrotation with said first and second drive members,

the periphery of one of said coupling members being circular coaxiallywith said power driven member and having a notch formed therein,

and in which said releasable means comprises a pawl pivoted to the othercoupling member and having a tooth engageable with said notch to connectsaid first and second coupling members for rotation in unison; and

an outward projection on said pawl, and

wherein said releasing means comprises:

a displaceable stop on said frame which, when displaced from an inactiveto an active position, is engaged by said projection thereby disengagingsaid tooth and stopping said first drive member in said predeterminedangular position with respect to said frame.

3. The loom defined in claim 2, further comprising a fixed stop on saidframe spaced from said displaceable stop and engageable by saidprojection in the disengaged condition of said tooth to prevent forwardrotation of said first drive member away from said predetermined angularposition with respect to said frame.

4. The loom defined in claim 1, wherein said manually actuable circuitmeans comprises first manually operable control means connected to saidcontactor means for causing continuous forward rotation of saidpower-driven member with said coupling means engaged during normalweaving operations and separate self-releasing second manually operablecontrol means connected to said contactor means for causing limitedforward rotation of said power-driven member during weave-correctingoperations.

5. A drive control for a loom having a shedding mechanism operativelyconnected to a first shaft, means including batten means operativelyconnected to a second shaft; clutch means between said first shaft andsaid second shaft, means for automatically disengaging said clutch meansupon rotation of said first shaft from a predetermined angular positionin reverse direction; and a reversible electric motor for rotating saidfirst shaft, said drive control comprising forward contactor means forcausing forward running of said motor; reverse contactor means forcausing reverse running of said motor; circuit means for interruptingthe energizing circuit of said forward contactor means in response toweaving irregularities; an auxiliary relay having a holding circuit anda normally open contact arranged when closed to complete the energizingcircuit of said reverse contactor means; a cam controlled two contactswitch shiftable between a first position in which one of its contactsbridges said auxiliary relay contact and a second position in which itsother contact completes the energizing circuit of said auxiliary relayas well as said holding circuit thereof; resilient means for urging saidcam controlled switch towards said one position thereof; a cam memberrotatable with said first shaft for shifting said two contact switchagainst the action of said resilient means to said second positionthereof when said first shaft approaches a predetermined position inreverse direction; and a manually actuable two contact control switchmovable between a normal position in which one of its contacts completesthe energizing circuit of said auxiliary relay and an actuated positionin which its other contact completes the energizing circuit of saidreverse contactor means, the arrangement being such that when saidcontrol switch is moved to and maintained in said actuated positionthereof, after the motor has been stopped in response to weavingirregularities, said control switch will cause energization of saidreverse contactor means either through said one contact of said camcontrolled switch when the latter is initially in said one positionthereof, or alternatively through said auxiliary relay contact and saidone contact of said cam controlled switch when the latter is initiallyin said second position thereof, but will prevent said auxiliary relayfrom being energized upon shifting of said cam controlled switch to saidsecond position thereof during reverse rotation of said first shaftwhereby to cause said cam controlled switch to interrupt theenergization of said reverse contactor means.

6. A drive control for a loom having a first rotatable shaft, a sheddingmechanism operatively connected to said first shaft; a second rotatableshaft; a plurality of individual mechanisms including batten meansoperatively connected to said second shaft; a clutch releasablyinterconnecting said first shaft and said second shaft; a reversibleelectric motor for selectively rotating said first shaft in the forwarddirection for normal motion of the loom or in the reverse direction forreverse motion of said shedding mechanism; drive control means forautomatically disengaging said clutch as said first shaft rotates into apredetermined angular position thereof in said reverse direction, saiddrive control means comprising a control circuit connected to a currentsource and including a plurality of parallel branches connected togetherat each end, a forward contactor in a first one of said branceseffective when energized to cause said motor to rotate said first shaftin said forward direction; a reverse contactor in a second brancheffective when energized to cause said motor to rotate said first shaftin said reverse direction; a first contact in said first branch; alocking relay in a third branch effective when energized to close saidfirst contact to thereby energize said forward contactor; circuit meansfor interrupting said third branch in response to weaving irregularitiesso as to cause said locking relay to open said first contact; a normallyclosed second contact in said second branch, a normally open thirdcontact in a fourth branch, a normally open fourth contact arranged whenclosed to bridge said second contact; a control relay in said fourthbranch effective when energized to close said fourth contact; a cammember connected for rotation with said first shaft; a movable actuating member for both said second contact and said third contactdisplaceable between an inoperative position in which said actuatingmember is out of the path of said cam member and an operative positionin which said actuating member is engageable by said cam member so as toopen said second contact and close said third contact as said firstshaft approaches said predetermined angular position thereof in thereverse direction; electromagnetically operated means controlled by saidlocking relay so as to cause displacement of said actuating member tosaid operative position thereof upon interruption of said third branch;and a manually actuated switch movable between a normal position inwhich it interrupts said second branch and completes said fourth branchand an actuated position in which it completes said second branch, andinterrupts said fourth branch, said switch being effective when moved tosaid actuated position thereof to cause energization of said reversingcontactor as long as either said second contact or said fourth contactremains closed.

7. A drive control according to claim 6, further comprising a connectionextending from a point of said first branch between said first contactand said forward contactor to a point of said second branch between saidsecond contact and said fourth contact; a further manually actuatedswitch movable between a normal position in which it interrupts saidconnection and completes said fourth branch and an actuatetd position inwhich it completes said connection and interrupts said fourth branch,said further switch being effective when moved to said actuated positionthereof to cause energization of said forward contactor as long as saidsecond contact is closed, a normally closed fifth contact in said secondbranch in series with said reverse contactor; a second movable actuatingmember associated with said fifth contact; and a cam disc connected forrotation with said second shaft and engageable with said secondactuating member so as to cause the latter to open said fifth contactwhen both said first and second shafts are in an angular position remotefrom said predetermined angular position of said first shaft.

8. In a loom having a shedding mechanism operatively connected to afirst drive shaft and a reciprocable lay operatively connected to asecond drive shaft; a drive control comprising a reversible electricmotor for normally rotating said first shaft in a forward direction;disengageable means for coupling said second shaft to said first shaftfor rotation therewith; stop means movable between an inactive positionand an active position in which it becomes engageable with said couplingmeans at a predetermined angular position of said first shaft to causedisengagement of said coupling means during reverse rotation of saiddrive shafts, said second shaft thereupon remaining stationary; anelectrical circuit including electromagnetically actuated means forautomatically stopping forward rotation of said motor and simultaneouslymoving said stop means into said active position in response to weavingirregularities; and manually controllable electromagnetically actuatedmeans for causing said motor after said automatic stopping thereof andwith said clutch means disengaged, to rotate said first shaft in saidreverse direction with said second shaft maintaining said lay withdrawnfrom the fell of the fabric being woven by said loom to permit themanual removal of individual weft threads released by reverse operationof said shedding mechanism.

9. A loom according to claim 8, further comprising cam-actuated switchmeans connected to said manually controllable means; and in whichmanually operable nonlocking switch means are included in said manuallycontrollable means, said cam-actuated means being driven by said motorand limiting reverse rotation of said first shaft to a predeterminedangular displacement corresponding to a single shed reversal by saidshedding mechanism in response to a single continuous actuation of saidnonlocking switch means, said shedding mechanism being positioned bysaid cam-actuated switch means to permit removal of an individual weftthread after each continuous actuation of said nonlocking switch means.

References Cited UNITED STATES PATENTS 2,421,539 6/1947 Clarke 1391.42,639,732 5/1953 Moessinger 139-1.4 2,715,920 8/1955 Butler et al.139336 2,810,402 10/1957 Godschalx 1391.4 2,962,056 11/1960 Paul et al.139136 3,095,015 6/1963 Cuiengnet 1391.4 3,159,186 12/1964 Juillard139127 3,237,648 3/1966 Grisay 1391.4

MERVIN STEIN, Primary Examiner.

JAMES KEE CHI, Assistant Examiner.

